Investigation of a trapezoidal microchannel for hydrodynamic detachment of cells or biomolecules.

Fluid-based non-specific adsorption (NSA) methods and cell adhesion studies both use hydrodynamic forces to detach biomolecules or cells. To address the limitations in current microfluidic detachment assays and NSA removal methods, a trapezoidal microchannel was investigated as a hydrodynamic method of cell or biomolecule detachment. This design utilizes the characteristic pressure-driven flow of microfluidics to detach cells or biomolecules at the narrow region of interest while enabling flexibility in the rest of the channel with larger height and low shear stress. A fluid dynamics analysis was performed analytically and using computational fluid dynamics simulations to compare the wall shear stress and pressure drop of straight microchannels with the proposed design. The results demonstrated the trapezoidal microchannel can produce a high wall shear stress similar to a straight microchannel with the same height at the region of interest (50 um), while conserving pressure loss, and holding a larger fluid volume